DK171190B1 - Multiple speaker with piezoelectric speaker unit - Google Patents
Multiple speaker with piezoelectric speaker unit Download PDFInfo
- Publication number
- DK171190B1 DK171190B1 DK251586A DK251586A DK171190B1 DK 171190 B1 DK171190 B1 DK 171190B1 DK 251586 A DK251586 A DK 251586A DK 251586 A DK251586 A DK 251586A DK 171190 B1 DK171190 B1 DK 171190B1
- Authority
- DK
- Denmark
- Prior art keywords
- speaker
- membrane
- piezoelectric
- loudspeaker unit
- diaphragm
- Prior art date
Links
- 239000000919 ceramic Substances 0.000 claims abstract description 12
- 230000005855 radiation Effects 0.000 claims abstract description 10
- 239000012528 membrane Substances 0.000 claims description 12
- 230000001681 protective effect Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000009429 distress Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
- H04R9/06—Loudspeakers
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/22—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only
- H04R1/24—Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges
Landscapes
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Piezo-Electric Transducers For Audible Bands (AREA)
- Obtaining Desirable Characteristics In Audible-Bandwidth Transducers (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
- Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
- Cosmetics (AREA)
- Percussion Or Vibration Massage (AREA)
- Dental Preparations (AREA)
- Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
Description
i DK 171190 B1in DK 171190 B1
Opfindelsen angår en multipel højttaler af den i krav l's eller krav 2's indledning angivne art. I højttaleren ifølge opfindelsen er en piezoe1ektri sk højtoneen-hed, d.v.s. højtonedel, fastholdt ved hjælp af en un-5 derstøtning, som tillader fuld udnyttelse af den bagud- gående bølge, som udsendes af den keramiske skive og respektive koniske membran, idet højttalerens hovedmembran anvendes som en reflekterende overflade uden overbelastning af hovedhøjttalerens svingspole.The invention relates to a multiple speaker of the kind set forth in claim 1 or claim 2. In the loudspeaker according to the invention, a piezoelectric loudspeaker unit, i.e. loudspeaker portion, retained by an auxiliary support allowing full utilization of the backward wave emitted by the ceramic disc and respective tapered membrane, using the speaker's main diaphragm as a reflective surface without overloading the main speaker's swivel coil.
10 for yderligere forklaring af højttaleren ifølge opfin delsen er der behov for at give en kort beskrivelse af det tekniske stade inden for lydgengi verområdet.10 for further explanation of the speaker according to the invention, there is a need to provide a brief description of the technical state of the art in the field of sound reproduction.
Til korrekt gengivelse af høje frekvenser bør en højttaler have en temmelig lille membran, medens gengivelse 15 af lave frekvenser på den anden side kræver en membran af betragtelige dimensioner. Når man derfor tilstræber en optimal lydgengivelse, anvendes sædvanligvis en samling på flere passende anbragte højttalere i stedet for at anvende blot én højttaler til at gengive hele 20 det hørbare frekvensområde med kvalitet: Nogle højtta lere med store dimensioner, som er egnet til gengivelse af lave frekvenser, kaldes normalt "woofers", medens andre med små dimensioner, som er egnet til gengivelse af høje frekvenser normalt kaldes højtoneenheder.For proper reproduction of high frequencies, a speaker should have a rather small diaphragm, while reproduction 15 of low frequencies, on the other hand, requires a diaphragm of considerable dimensions. Therefore, when striving for optimum sound reproduction, a collection of several appropriately arranged speakers is usually used instead of using just one speaker to reproduce the entire 20 audible frequency range with quality: Some high-dimension speakers suitable for low reproduction frequencies, are usually called "woofers", while others with small dimensions suitable for reproducing high frequencies are usually called loudspeakers.
25 Den multiple højttalergruppe indeholder bi-foniske ko- aksialhøjttalere, som har to gengivelsesanordninger, som er helt uafhængige af hinanden men koaksialt monteret, den ene udstyret med en stor membrankegle, medens den anden er udstyret med en mindre membrankegle, som 30 er anbragt umiddelbart foran og med samme akse som den store membran.The multiple speaker array contains biphonic coaxial speakers which have two display devices which are completely independent of each other but coaxially mounted, one equipped with a large diaphragm cone, while the other is equipped with a smaller diaphragm cone which is disposed immediately. front and with the same axis as the large diaphragm.
I nogle bi-foniske koaks i a 1 høj11a 1ere er der anbragt 2 DK 171190 B1 en piezoelektrisk højtoneenhed, nemlig ved at anvende en keramisk skivegenerator for lydbølger, beliggende inden for en lille beskyttelses- og understøtningskurve, som er fastgjort til en del af hovedhøj11a 1errammen 5 (d.v.s. den store højttaler), i overensstemmelse med en række konstruktionsløsninger: I nogle modeller er kurven understøttet af en aksial tap, medens der i andre modeller er optaget en understøtningskonsol fremstillet af en eller flere radiale eger, hvis ender skal 10 positioneres og fastgøres på hovedhøjttalerkurven .In some bi-phonetic coax ia 1 high11a 1, a piezoelectric high-tone unit is arranged, namely by using a ceramic disc generator for sound waves, located within a small protection and support curve which is attached to a portion of the main high11a frame. 5 (ie the large speaker), in accordance with a number of design solutions: In some models, the curve is supported by an axial pin, while in other models a support bracket is made of one or more radial spokes whose ends must be positioned and fixed. on the main speaker curve.
Begge de netop beskrevne konstruktionsløsninger fremby-der nogle fælles problemer og nogle specifikke problemer .Both of the design solutions just described present some common problems and some specific problems.
F.eks. er den ovennævnte centrale understøtningstap 15 ikke mekanisk pålidelig; især når man tager det billi ge materiale, som benyttes til dens fremstilling, i betragtning, hvilket materiale hovedsageligt er plast, som med nød og næppe er bestandigt over for temperaturen, det kan bøjes til siden, indtil det berører hoved-20 højttalerspolen, hvilket medfører friktion imellem de lene, som kommer i berøring med hinanden og umiddelbart medfører en utilladelig knitrende støj, i værste tilfælde blokering af den store membran.For example. the aforementioned central support pin 15 is not mechanically reliable; especially when considering the inexpensive material used for its manufacture, which material is mainly plastic, which with distress and barely resistant to temperature, can be bent to the side until it touches the main speaker coil, which causing friction between the joints which come into contact with each other and immediately cause an unmistakable crackling noise, in the worst case, blocking the large diaphragm.
Endvidere tillader begge de ovennævnte understøtnings-25 systemer ikke installeringen af højtoneenheden helt inden for hovedhøjttalerens membran på en sådan måde, at kanterne af de to keglers i snit største diametre faktisk er i samme plan. Dette skyldes de samlede dimensioner af beskyttelses- og understøtningskurven ved 30 den piezoelektnske hø jtoneenhed .Furthermore, both of the above-mentioned support systems do not allow the installation of the loudspeaker unit completely within the main speaker's diaphragm in such a way that the edges of the two cones' largest diameters in section are actually in the same plane. This is due to the overall dimensions of the protection and support curve at the piezoelectric loudspeaker unit.
Det alvorligste problem, som kan opstå i begge de før omtalte systemer beror imidlertid på den kendsgerning, 3 DK 171190 B1 at lydbølgerne, som udsendes fra bagsiden af den keramiske skiv/e og ved hjælp af den piezoelektrisk højtone-enheds koniske membran, ikke kan udnyttes fuldt ud på grund af tilstedeværelsen af førnævnte understøtnings-5 kurv. Hvis disse bølger kunne blive reflekteret fremad, ville den faktiske strålingsimpedans af lydkilden blive f orøget.However, the most serious problem that can arise in both the systems mentioned above is due to the fact that the sound waves emitted from the back of the ceramic disc / e and by means of the piezoelectric high-tone conical membrane cannot is fully utilized due to the presence of the aforementioned support 5 basket. If these waves could be reflected forward, the actual radiation impedance of the sound source would be increased.
Med dette i erindring er et alternativ til de to ovennævnte løsninger allerede blevet foreslået, hvor under-10 støtningen af den piezoelektnske højtoneenhed er belig gende i en koaksial position foran hovedhøjttalerkeglen.With this in mind, an alternative to the above two solutions has already been proposed, where the support of the piezoelectric loudspeaker unit is in a coaxial position in front of the main speaker cone.
Ifølge denne alternative løsning er den piezoelektnske højtoneenhed ikke beliggende inden i kurven, men dens keramiske skive er tæt forbundet til hovedhøjttalerspo-13 lens mobile understøtning, idet membranen for hovedhøjt taleren så kan fungere som en reflekterende overflade for udstrålingerne, som udsendes fra bagsiden af højto-neenhedskeglen, men ikke for de udstrålinger, som udsendes af den keramiske skive, som er fastgjort til hoved-20 højttalerspolens bevægelige understøtning.According to this alternative solution, the piezoelectric loudspeaker unit is not located within the curve, but its ceramic disc is tightly connected to the headphone coil's mobile support, the main loudspeaker diaphragm can then act as a reflective surface for the radiations emitted from the back of the loudspeaker. -the unit cone, but not for the radiations emitted by the ceramic disk attached to the movable support of the main 20 speaker coil.
I tilknytning til den begrænsede udnyttelse af bølgerne, som udsendes fra bagsiden af den piezoelektnske højtoneenhed, medfører den sidstnævnte løsning klart en overbelastning af hovedhøjttalerspolens bevægelige 25 understøtning. Selv om denne er minimal, er en forøget størrelse af magneten ikke desto mindre nødvendig, hvilket fører til en bemærkelsesværdig forøgelse af de endelige fremstillingsudgifter.Due to the limited use of the waves emitted from the back of the piezoelectric loudspeaker unit, the latter solution clearly causes an overload of the movable support of the main speaker coil. Even though this is minimal, an increased size of the magnet is nevertheless necessary, leading to a remarkable increase in final manufacturing costs.
Formålet med opfindelsen er at tilvejebringe et middel 30 til at understøtte den piezoelektnske højtoneenhed, som, uden overbelastning af hovedhøjttalerspolens bevægelige understøtning tillader udnyttelsen af strålingen, 4 DK 171190 B1 som udsendes fra bagsiden af den keramiske skive og som udsendes med keglen. Membranen bag hovedhøjttaleren virker som en reflekterende overflade, og desuden er den piezoelektnske højtoneenheds samlede dimensio-5 ner begrænset på en sådan måde, at hele sidstnævnte kan passe i hovedhøjttalerkeglen.The object of the invention is to provide a means 30 for supporting the piezoelectric loudspeaker unit which, without overloading the movable support of the main speaker coil, allows the utilization of the radiation emitted from the back of the ceramic disk and emitted with the cone. The diaphragm behind the main speaker acts as a reflective surface, and, furthermore, the overall dimensions of the piezoelectric loudspeaker unit are limited in such a way that the whole latter can fit into the main speaker cone.
Dette opnås ifølge opfindelsen ved, at den indledningsvis angivne multiple højttaler er ejendommelig ved det i krav l's eller krav 2's kendetegnende del angivne.This is achieved according to the invention in that the multiple loudspeaker initially stated is characterized by the characteristic part of claim 1 or claim 2.
10 Løsningen er baseret på den kendsgerning, at den piezo- elektriske højtoneenhed er anbragt foran hovedhøjtta-lerkeglen uden den sædvanlige understøtning og beskyttelseskurv. I stedet anvendes et andet understøtnings-middel, som ikke skærer eller forstyrrer den fra bagsi-15 den af den piezoelektnske højtoneenhed udsendte strå ling eller hæmmer den fremadgående refleksion af strålingen ved hjælp af hovedhøjttalermembranen.10 The solution is based on the fact that the piezoelectric loudspeaker unit is placed in front of the main speaker cone without the usual support and protection basket. Instead, another support means is used which does not cut or interfere with the radiation emitted from the back of the piezoelectric loudspeaker unit or inhibit the forward reflection of the radiation by the main speaker membrane.
Ifølge en udførelsesform for opfindelsen er den piezo-elektnske højtoneenhed uden en kurv understøttet af 20 en edderkopformet konsol med radiale eger, hvis ender er fastgjort til hovedhøjttalerkurven.According to an embodiment of the invention, the piezoelectric loudspeaker unit without a basket is supported by a spider-shaped bracket with radial spokes, the ends of which are attached to the main speaker curve.
Ifølge en anden udførelsesform for opfindelsen er den piezoelektnske højtoneenhed fastgjort på bagsiden af beskyttelsesristen, som sædvanligvis dækker åbningen 25 på frontpanelet, hvorpå højttaleren er monteret.According to another embodiment of the invention, the piezoelectric loudspeaker unit is attached to the back of the protective grating, which usually covers the opening 25 of the front panel on which the speaker is mounted.
Opfindelsen skal i det følgende nærmere beskrives med henvisning til tegningen, hvorpå to foretrukne udførelsesformer ifølge opfindelsen er vist skematisk, og hvorpå : 30 fig. 1 er tværsnit gennem aksen for en udførel sesform for en bi-fonisk koaksial højttaler ifølge opfindelsen, 5 DK 171190 B1 og fig. 2 er et tværsnit gennem aksen af en anden udførelsesform for en bi-fonisk koaksial højttaler ifølge opfindelsen.The invention will now be described in more detail with reference to the drawing, in which two preferred embodiments of the invention are shown diagrammatically, and in which: FIG. 1 is a cross-section through the axis of an embodiment of a bi-phonic coaxial loudspeaker according to the invention; FIG. 2 is a cross-section through the axis of another embodiment of a biphonic coaxial speaker according to the invention.
5 Den på tegningsfigurerne viste højttaler er fremstillet af to uafhængige gengivelsesanordninger, som er monteret koaksialt og i overensstemmelse med traditionelle konstruktionsmetoder for bi-foniske koaksiale højttalere .5 The speaker shown in the drawings is made of two independent reproduction devices which are coaxially mounted and in accordance with traditional design methods for bi-phonetic coaxial speakers.
10 Hovedsvingspo1e-høj11a 1eren, som er egnet til gengivel se af mellem- til lave frekvenser, er fremstillet af en kurv 1, som understøtter den kegleformede mebran 2 indvendigt og centreringsanordningen 3, medens den tillader svingspolen at bevæge sig i længderetningen, 13 idet den sikrer, at svingspolen altid er perfekt centre ret i 1uftme 1lemrummet og ikke berører de to polsko.The head oscillator high 11a suitable for reproducing medium to low frequencies is made of a basket 1 which supports the cone-shaped diaphragm 2 internally and the centering device 3 while allowing the oscillating coil to move longitudinally, 13 ensures that the swivel coil is always perfectly centered in the 1ftm 1lm space and does not touch the two pole shoes.
Den yders te polsko er vist som en ringformet polsko 4 og den indre polsko er en cylindrisk polsko 5.The outer pole shoe is shown as an annular pole shoe 4 and the inner pole shoe is a cylindrical pole shoe 5.
Henvisningsta 11et 8 angiver en antistøvplade, som dæk-20 ker ved forsiden af den bevægelige understøtningsmuffe 9 for svingspolen, som ikke er vist på figuren.Reference numeral 8 denotes an anti-dust plate which covers at the front of the movable support sleeve 9 of the pivot coil, not shown in the figure.
I fig. 1 er den anden piezoelektnske højttaler, som er egnet til højfrekvensgengivelse, karakteriseret ved den kendsgerning, at den kun er fremstillet af den ke-25 ramiske skive 10 og dens respektive kegle 11, som hol des i en position koaksialt med og foran hovedhøjttalerens membran 2 ved hjælp af en understøtningskonsol 12, som igen er fremstillet af en central ringformet flange, hvorfra en eller flere radiale eger udgrenes, 30 i niveau med flangen, hvilke egers ender er knyttet sammen med hovedhøjttalerens understøtningskurv 1.In FIG. 1, the second piezoelectric speaker suitable for high frequency reproduction is characterized by the fact that it is made only of the ceramic disc 10 and its respective cone 11 held in a position coaxially with and in front of the membrane of the main speaker 2 by means of a support bracket 12, which in turn is made of a central annular flange from which one or more radial spokes are branched out, 30 at the level of the flange, the ends of which are connected to the support basket 1 of the main speaker.
6 DK 171190 B16 DK 171190 B1
Ued det punkt, hvor diameteren er størst, er den piezo-elektnske højtoneenheds kegle 11 nærmere bestemt limet ved kanten til en svampering 13, som virker som en dæmper, som igen er limet på bagsiden af førnævnte centra-5 le ringformede flange.Specifically, at the point where the diameter is greatest, the piezo-electric loudspeaker unit cone 11 is glued at the edge to a sponge ring 13, which acts as a damper, which in turn is glued to the back of the aforementioned central annular flange.
Af den i fig. 2 viste anden udførelsesform for opfindelsen bemærkes det, hvorledes den piezoelektnske højtone-enhed er understøttet i en koaksial position foran hovedhø jttalermembranen 2 ved hjælp af beskyttelsesristen 10 14, som sædvanligvis dækker hullet på frontpanelet, hvorpå højttaleren er monteret.From the one shown in FIG. 2, it is noted how the piezoelectric loudspeaker unit is supported in a coaxial position in front of the main speaker membrane 2 by means of the protective grating 10 14, which usually covers the hole on the front panel on which the speaker is mounted.
I denne anden udførelsesform er svamperingen 13, hvortil kanterne af den piezoelektnske højtoneenhedskegle II skal fastgøres, limet til en overflade, som er s æ r - 15 lig tilvejebragt til formålet, på indersiden af risten 14. Nævnte rist kan endog have et horn 15 på den udvendige åbning, hvorpå nævnte svampering 13 kan være limet.In this second embodiment, the sponge ring 13, to which the edges of the piezoelectric loudspeaker cone II are to be attached, is glued to a surface which is particularly provided for the purpose on the inside of the grate 14. Said grate may even have a horn 15 of the outer opening on which said sponge ring 13 may be glued.
Det er klart, at opfindelsen kan benyttes inden for mu 111 høj11a 1erområdet i almindelighed, ikke nødvendig-20 vis bi-foniske og/eller koaksiale højttalere.It is to be understood that the invention may be used in the art of the 111-111 general area, not necessarily biphonic and / or coaxial speakers.
Claims (2)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT00625/85A IT1187062B (en) | 1985-09-02 | 1985-09-02 | MULTIPLE SPEAKER, WITH PIEZOELECTRIC "TWEETER" SUPPORTED WITH MEANS THAT ALLOW THE EXPLOITATION OF THE MEMBRANE OF THE MAIN SPEAKER AS THE REFLECTIVE SURFACE OF THE RADIATION EMITTED REAR FROM THE CERAMIC DISC AND THE "TWE" MEMBRET |
| IT6258585 | 1985-09-02 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DK251586D0 DK251586D0 (en) | 1986-05-29 |
| DK251586A DK251586A (en) | 1987-03-03 |
| DK171190B1 true DK171190B1 (en) | 1996-07-15 |
Family
ID=11293510
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK251586A DK171190B1 (en) | 1985-09-02 | 1986-05-29 | Multiple speaker with piezoelectric speaker unit |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0220354B1 (en) |
| JP (1) | JPH0738752B2 (en) |
| KR (1) | KR950002765B1 (en) |
| AT (1) | ATE65149T1 (en) |
| CA (1) | CA1287394C (en) |
| DE (1) | DE3583442D1 (en) |
| DK (1) | DK171190B1 (en) |
| ES (1) | ES8707839A1 (en) |
| FI (1) | FI86941C (en) |
| IT (1) | IT1187062B (en) |
| NO (1) | NO169930C (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3167153B2 (en) * | 1991-09-30 | 2001-05-21 | パイオニア株式会社 | Speaker spacer |
| GB9317345D0 (en) * | 1993-08-20 | 1993-10-06 | Centralforce Ltd | Loudspeaker |
| AUPS279202A0 (en) * | 2002-06-05 | 2002-06-27 | Sportzwhistle Pty Ltd | Transducer mounting |
| JP5392335B2 (en) * | 2011-10-12 | 2014-01-22 | 株式会社デンソー | Vehicle presence reporting device |
| KR101451687B1 (en) * | 2013-08-20 | 2014-10-22 | 임창수 | two way speaker having coaxial effect |
| US11627416B2 (en) | 2021-08-27 | 2023-04-11 | Apple Inc. | Two-way integrated speaker with piezoelectric diaphragm as tweeter |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52145215A (en) * | 1976-05-28 | 1977-12-03 | Nippon Gakki Seizo Kk | Complex type speaker |
| JPS55154899A (en) * | 1979-05-22 | 1980-12-02 | Pioneer Electronic Corp | Compound loudspeaker |
| US4283606A (en) * | 1979-07-16 | 1981-08-11 | Cerwin Vega, Inc. | Coaxial loudspeaker system |
| JPS56112196A (en) * | 1980-02-08 | 1981-09-04 | Matsushita Electric Ind Co Ltd | Composite type speaker |
| JPS5753798U (en) * | 1980-09-11 | 1982-03-29 | ||
| JPS5912699A (en) * | 1982-07-13 | 1984-01-23 | Matsushita Electric Ind Co Ltd | Composite type speaker |
| US4475014A (en) * | 1982-09-13 | 1984-10-02 | Harman-Motive Inc. | Acoustical transducer |
| JPS5963592U (en) * | 1982-10-20 | 1984-04-26 | フォスタ−電機株式会社 | composite speaker |
-
1985
- 1985-09-02 IT IT00625/85A patent/IT1187062B/en active
- 1985-09-09 DE DE8585830227T patent/DE3583442D1/en not_active Expired - Fee Related
- 1985-09-09 EP EP85830227A patent/EP0220354B1/en not_active Expired - Lifetime
- 1985-09-09 AT AT85830227T patent/ATE65149T1/en not_active IP Right Cessation
-
1986
- 1986-05-29 DK DK251586A patent/DK171190B1/en not_active IP Right Cessation
- 1986-05-30 FI FI862323A patent/FI86941C/en not_active IP Right Cessation
- 1986-06-05 ES ES555745A patent/ES8707839A1/en not_active Expired
- 1986-06-12 KR KR1019860004662A patent/KR950002765B1/en not_active IP Right Cessation
- 1986-06-18 NO NO862429A patent/NO169930C/en not_active IP Right Cessation
- 1986-07-08 JP JP61158908A patent/JPH0738752B2/en not_active Expired - Lifetime
- 1986-07-11 CA CA000513575A patent/CA1287394C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0738752B2 (en) | 1995-04-26 |
| EP0220354B1 (en) | 1991-07-10 |
| NO862429D0 (en) | 1986-06-18 |
| FI86941C (en) | 1992-10-26 |
| CA1287394C (en) | 1991-08-06 |
| ATE65149T1 (en) | 1991-07-15 |
| ES8707839A1 (en) | 1987-09-01 |
| FI862323A0 (en) | 1986-05-30 |
| EP0220354A3 (en) | 1988-01-07 |
| FI86941B (en) | 1992-07-15 |
| DE3583442D1 (en) | 1991-08-14 |
| NO169930C (en) | 1992-08-19 |
| KR950002765B1 (en) | 1995-03-24 |
| NO169930B (en) | 1992-05-11 |
| KR870003670A (en) | 1987-04-18 |
| IT1187062B (en) | 1987-12-16 |
| EP0220354A2 (en) | 1987-05-06 |
| IT8500625A0 (en) | 1985-09-02 |
| NO862429L (en) | 1987-03-03 |
| DK251586A (en) | 1987-03-03 |
| DK251586D0 (en) | 1986-05-29 |
| ES555745A0 (en) | 1987-09-01 |
| FI862323A (en) | 1987-03-03 |
| JPS6253590A (en) | 1987-03-09 |
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| PBP | Patent lapsed |